tbuckley/cabot-search huggingface dataset:
Abstract P2011: Reduced Activity Of Activin Like Kinase 1 (ALK1) Increases Mortality And Myocardial Rupture After Acute Myocardial Infarction
Authors: Shreyas Bhave, Michele Esposito, Lija Swain, Xiaoying Qiao, Gregory Martin, Kay Everett, Navin K Kapur
Journal: Circulation Research (2023)

Introduction: Acute myocardial infarction (AMI) is a primary cause of heart failure (HF). Transforming growth factor beta (TGFβ) plays a central role in cardiac remodeling after AMI. Reduced activity of the TGFβ Type I receptor, activin like kinase (ALK)-1 promotes cardiac fibrosis in murine models of heart failure. A functional role for ALK1 in post-infarct cardiac remodeling remains poorly understood. We hypothesize that reduced ALK1 activity reduces survival and promotes cardiac fibrosis after AMI. Methods: AMI was induced by left coronary ligation in wild type (WT), and ALK+/- mice. After 14 days, LV function was assessed using conductance catheters and myocardial ALK1 signaling was quantified. Using siRNAs targeting ALK1 in in human cardiac fibroblasts (H-CFs), we further tested the role of ALK1 in cardiac fibrosis. Results: Reduced ALK1 activity significantly reduced survival compared to WT (p= 0.008 respectively) after AMI. ALK1 mice demonstrated a higher rate of cardiac rupture compared to WT after AMI (0% vs 85.7%). Both WT ad ALK1+/- mice demonstrated reduced LV ejection fraction and stroke work compared to sham controls (p=0.001 and p=0.0001 respectively). Profibrotic SMAD3 signaling was increased and antifibrotic SMAD1 signaling decreased in ALK1-/+ (pSMAD3, p=0.03, pSMAD1, p=0.003) mice 14 days after AMI. Reduced SMAD1 signaling was directly associated with increased myocardial Type 1 collagen protein levels in ALK1-/+ (R2=0.42, p=0.01) mice compared to WT. Myocardial levels of the TGFb1 co-receptor, endoglin, were increased significantly in ALK+/- as compared to WT (p=0.001) after AMI. Activity of MMP9 was increased in ALK1+/- mice, but protein levels were not affected 2 weeks after MI. Conclusion: We identify for the first time that loss of ALK1 activity increases cardiac rupture and mortality after AMI. These findings identify a novel functional role for ALK1 as a determinant of post-infarct survival and cardiac remodeling and implicate ALK1 as a potential therapeutic target to improve survival after AMI.
Abstract P1169: BubR1 Regulates Cardiac Development Through CamkII <i>In Vivo</i>
Authors: Renju Pun, Sylar Takafuji, Rexton Suzuki, Aradhana Thapa, Michael H Kim, Brian North
Journal: Circulation Research (2023)

Congenital heart defects (CHD), which represent the most common type of congenital defects, are found in 8 out of 1000 births each year in the US. Aneuploidy, defined as an abnormal number of chromosomes in a cell, is the largest contributor to CHD. Defects in mitotic regulators can promote aneuploidy. For instance, mutations in the mitotic checkpoint protein BubR1 can lead to mosaic variegated aneuploidy (MVA). MVA patients display varied phenotypes including growth deficiency and a shortened lifespan. In addition, some patients develop CHDs such as atrioventricular septal defects. To determine whether BubR1 regulates cardiac development we carried out timed matings to harvest heart tissue at various embryonic stages. We found that BubR1 expression dramatically increases in the mouse heart through embryonic development. We engineered a conditional BubR1 knockout mouse model using the Cre-lox system which allows for the generation of cardiac-specific BubR1 knockout animals when crossing this BubR1 fl/fl mice to Nkx2.5-cre mice, which mediates deletion of BubR1 beginning at E7.5. Interestingly, we did not observe any homozygous cardiac-specific BubR1 knockout mice in newborn litters, suggesting that loss of BubR1 in the developing heart is embryonic lethal (n = 120, P &lt; 0.01). We observed that deletion of BubR1 in the embryonic heart leads to cardiac malformations including the absence of trabeculations and reduction in the size of ventricles. Immunofluorescence studies reveal that cardiac-specific BubR1 knockout embryos have an increase in cell death as measured by the apoptosis marker cleaved-caspase 3. These embryos also show an increase in the apoptosis regulator CaMKII, whose upregulation has been previously tied to an increase in cardiomyocyte apoptosis. Therefore, we conclude that BubR1 suppresses the expression of CaMKII in the developing heart to regulate apoptosis during cardiogenesis. Taken together, our data suggest that BubR1 is a critical regulator for cardiac development in vivo , and its mutation or loss may contribute to the development of CHDs.
Abstract P2137: Comparative Effectiveness And Safety Of Rivaroxaban Versus Warfarin In Valvular Atrial Fibrillation: A Systematic Review And Meta-Analysis
Authors: Ziad Rafe H Affas, Sneha Annie Sebastian, Banan Rasool, Inderbir Padda, Shwan Amen, Jelena Arnautovic, Gurpreet Johal
Journal: Circulation Research (2023)

Introduction: Patients with valvular atrial fibrillation (AF), which refers to moderate to severe mitral stenosis or mechanical prosthetic heart valves, have an increased risk of ischemic stroke and systemic embolism, which mandates the need for long-term anticoagulation. Still, there are no clear consensus guidelines on the indications of anticoagulation therapy in valvular AF. We aimed to compare the effectiveness of rivaroxaban, a common direct-acting oral anticoagulant (DOAC), to warfarin for preventing thromboembolism in valvular AF patients. Methods: We performed a systematic search of the following databases; PubMed, Cochrane Library, Google Scholar, and EMBASE from inception until February 06, 2023. Results: After screening 389 studies, 8 studies with 68,847 patients have been included in the final analysis. Our meta-analysis did not reveal a significant difference in the occurrence of all-cause mortality between patients who received rivaroxaban and those who received warfarin [RR, 0.97 (95% CI: 0.53-1.76]), p =0.91]. On analysis of the individual studies, rivaroxaban was non-inferior to warfarin with a lower risk of bleeding events [RR, 0. 80 (95% CI: 0.62-1.04), p =0.72], myocardial infarction [RR, 0.56 (95% CI: 0.13-2.47), p =0.44], and stroke/systemic embolism [RR, 0.54 (95% CI: 0. 11-2.55), p = 0.43]. But there was no statistically significant difference between the two groups. Conclusions: With a decreased risk for major adverse events, rivaroxaban appears to have a favorable safety profile, making them a promising alternative to warfarin in treating patients with valvular AF. However, more randomized clinical trials are imperative.
Abstract P1047: The Extracellular Matrix Metalloproteinase Inducer And The Membrane Type 1 Matrix Metalloproteinase In Marfan Syndrome Related Thoracic Aortic Aneurysm
Authors: Andrew R Peterson, Kyle C Alexander, Carlton Anderson, Joseph Parrish, Jacob G Boutros, Syed Mohsin Shah, John H Cannon, Jarret Peterson, Jaleel Townsend, Dalton J McGlamery, John S Ikonomidis, Adam W Akerman
Journal: Circulation Research (2023)

Objectives: Marfan Syndrome (MFS) is a connective tissue disorder commonly associated with Thoracic Aortic Aneurysms (TAAs). TAAs occur because of abnormal remodeling of the aortic extracellular matrix (ECM). The balance between matrix metalloproteinases (MMPs) and the Tissue Inhibitors of MMPs (TIMPs), regulates these processes. The extracellular MMP inducer (EMMPRIN), is a widely expressed glycoprotein capable of stimulating the production of various MMPs, suggesting a direct role in driving pathology. The Membrane Type-1 MMP (MT1-MMP) can cause proteolytic shedding of EMMPRIN. Therefore, we investigated this relationship in MFS TAA tissue and plasma and tested the hypothesis that a unique proteolytic profile may exist. Methods: Levels of EMMPRIN, MT1-MMP, MMP-2, MMP-9, MMP-3, MMP-8, TIMP-1, and TIMP-2 were measured in aortic tissue and plasma from MFS patients with TAA and compared to healthy controls. Following modification of the abundance and location of MT1-MMP in isolated primary aortic fibroblasts, secreted EMMPRIN was measured in conditioned culture media. Results: Compared to controls, EMMPRIN is elevated in MFS TAA tissue and reduced in the plasma. Elevation of EMMPRIN abundance in tissue does not induce MMP-3, MMP-8, or TIMP-1 expression. MT1-MMP and TIMP-2 are elevated in MFS TAA tissue. MMP-2 and MMP-9 are reduced in MFS TAA tissue while increased in the plasma. In aortic fibroblasts we found that MT1-MMP must be internalized from the plasma membrane for EMMPRIN secretion. Conclusions: Our findings indicate that the pathological consequences of MFS cause the shedding of EMMPRIN and its secretion from cells to be blocked, which leads to higher EMPRINN abundance in MFS TAA tissue. This process depends upon the cellular location of MT1-MMP. Taken together, these observations suggest that internalization of MT1-MMP from the plasma membrane is required for the cellular secretion of EMMPRIN from aortic fibroblasts.
Abstract P1041: Multiplexed Cardiotoxicity And Efficacy Screening Using Kinetic Image Cytometry Of Human Induced Pluripotent Stem Cell-derived Cardiomyocytes
Authors: Ranor Christian B Basa, Patrick McDonough, Ameena Pascua, Lilian Harrison, Ariel Wang, Jeffrey M Hilton, Randall S Ingermanson, Jeffrey H Price
Journal: Circulation Research (2023)

Traditionally, cardiotoxicity testing used low-throughput animal models which may not fully recapitulate human physiology. Stem cell technology enables screening in a more physiologically-relevant model system in less time and with less cost, but most current high-throughput screening modalities rely on whole-well or whole-field averaged data, which obfuscate the responses of individual hiPSC-cardiomyocytes (CMs). By measuring individual hiPSC-CMs, heterogenous responses that would otherwise be “averaged out” can be quantified, thus improving sensitivity. We previously published that the single-cell Kinetic Image Cytometry (KIC) methods developed at Vala Sciences predicted arrhythmogenic liability with an accuracy of 90% using intracellular Ca 2+ kinetics as a readout. In this study, we expand upon this methodology by loading metabolically matured hiPSC-CMs with Cal-520 (a green Ca 2+ dye) and BeRST-1 (a far red membrane voltage dye), acquiring interleaved movies of Ca 2+ and membrane potential at 60 Hz (30 Hz per channel). We then created image analysis algorithms to measure Ca 2+ transient (CT) and action potential (AP) kinetics, and to derive contraction measurements from those movies. To validate our approach, we exposed cells to isoproterenol, nifedipine, dofetilide, and butadiene 2-monoxime (BDM) at various concentrations. Isoproterenol increased beat rate, decreased both AP and CT durations, increased CT magnitude, and elicited a lusitropic effect. Nifedipine increased beat rate, decreased AP and CT durations, and reduced CT magnitude and contraction distance. Dofetilide reduced beat rate, prolonged APs and CTs, and increased contraction distance. BDM had multiple inhibitor effects on APs and CTs, and strongly reduced contraction. Thus, this multiplexed assay can quantify multiple effects of drugs on APs, CTs, and contraction, providing an unprecedented suite of information relevant to cardiosafety and efficacy.
Abstract P3103: Heart Failure In Menopause: Treatment With Rock Inhibitor And Atorvastatin
Authors: Gisele Zapata-Sudo, Jaqueline S Da Silva, Bruna Rocha, Tadeu Montagnoli, Rebeca S Cunha, Bianca Nascimento-Carlos, Carlos Fraga
Journal: Circulation Research (2023)

In advanced age, women tend to develop heart failure with preserved ejection fraction (HFpEF) due to estrogen depletion. The signaling pathway of ROCK is involved in cardiac complications consequent to female aging. Thus, this work investigated the comparative effects of atorvastatin and ROCK inhibitor, fasudil on the treatment of HFpEF induced by oophorectomy (OVX) in spontaneously hypertensive rats (SHR). Protocols were approved by the Animal Care and Use Committee at Universidade Federal do Rio de Janeiro. Under anesthesia with ketamine (80 mg/kg, i.p.) and xylazine (15 mg/kg, i.p.), female SHR were submitted to OVX procedure and after 8 wks were randomly orally treated with either vehicle or atorvastatin (40 mg/kg) or fasudil (10 mg/kg) during 4 wks. At the end of treatment, hemodynamic parameters were evaluated using echocardiography and LV catheterization. Cardiac tissues were collected for histologic analysis. Cardiac hypertrophy was reversed by treatment with atorvastatin or fasudil. Increased systolic pressure of LV was observed in SHR-OVX group (149.2 ± 7.9 mmHg), which was partially reduced by fasudil (123.4 ± 7.4 mmHg) and normalized by atorvastatin (94.5 ± 3.9 mmHg). Reduction of the increased diastolic dysfunction observed by echocardiogram was confirmed, since the recovery of the increased LV end diastolic pressure of SHR-OVX (32.1 ± 1.8 mmHg) occurred after treatment with atorvastatin (22.4 ± 9.6 mmHg) and fasudil (11.9 ± 2.4 mmHg). Fibrosis was observed because of the increased collagen deposition in SHR-OVX (6.2 ± 0.1%), with partial reduction with fasudil (4.4 ± 0.3%) and normalization after treatment with atorvastatin (1.9 ± 0.7%). Cell proliferation was evaluated using the p38 marker, where the percentage of nuclei marked was determined in relation to the total, through immunohistochemical technique. An increase in nuclear p38 in the SHR-OVX group was observed (23.2 ± 3.2%), however, the treatment with atorvastatin (12.1 ± 1.7%) and fasudil (5.3 ± 1.3%) reduced the nuclear p38 detection. In conclusion, atorvastatin and fasudil promoted recovery of HFpEF induced by estrogen depletion in SHR. Inhibition of ROCK signalling by atorvastatin could be involved in the reduction of diastolic dysfunction observed in OVX-SHR group.
Abstract P2026: Moderate Ethanol Consumption Causes Right Ventricular Hypertrophy And Pulmonary Hypertension Via The Pro-inflammatory Endothelin-interleukin Pathway
Authors: Mary K Donovan, Abdel A Abdel-Rahman
Journal: Circulation Research (2023)

The substantial increase in ethanol consumption since the Covid-19 pandemic has re-emphasized the need for extensive preclinical research on the cardiac and pulmonary effects of ethanol. Current knowledge is mostly based on ethanol effects on left ventricular (LV) function and blood pressure. Therefore, this preclinical study dealt with the effects of moderate ethanol consumption on right ventricular (RV) and pulmonary artery (PA) structure and function, and the implicated mechanisms in a pulmonary hypertension susceptible rat strain. Two groups of Sprague-Dawley (CD strain) male rats (n=7-8 each) received balanced liquid diet containing 5% ethanol (w/v) or pair-fed with isocaloric liquid diet for 8 weeks. This ethanol regimen resulted in clinically relevant blood ethanol concentration (39.8 + 1.9 mg/dL). Echocardiographic analysis showed progressive decreases in PA acceleration time/ejection time and increases in mean PA pressure (hallmarks of pulmonary hypertension) in ethanol-fed rats. Further, transthoracic echocardiography in long-axis orientation showed a significant increase in the RV internal diameter/left ventricular internal diameter during diastole (RVID-d/LVID-d), indicative of RV dilation in chronic ethanol-treated rats. Echocardiographic LV Mass/body weight and post-mortem Fulton’s index were higher in ethanol-fed rats, suggesting ethanol induced simultaneous LV and RV hypertrophy. Further, ethanol increased mean arterial pressure (measured at the end of the 8-weeks study). Ex vivo biochemical analyses showed upregulation of the vasoconstrictor/pro-inflammatory protein endothelin-1 (ET-1) and its downstream target IL-6 in the RV and lungs of ethanol-fed rats. Finally, ethanol reduced lung endothelin ETB receptor expression but had no effect on the ETA receptor, leading to higher ETA/ETB receptor ratio. Collectively, this study yields new insight into ethanol-evoked RV and pulmonary artery remodeling via the upregulation of the ET-1-IL-6 pathway.
Abstract P1079: Regeneration Of Primate Hearts With Human IPS Cell-derived Cardiac Spheroids
Authors: Hideki Kobayashi, Shugo Tohyama, Koichiro Kuwahara, Yuji Shiba, Keiichi Fukuda
Journal: Circulation Research (2023)

Background: Clinical application of human induced pluripotent stem cell-derived cardiomyocytes (hiPSC-CMs) for cardiac repair started with the epicardial delivery of engineered cardiac tissue; however, the feasibility of the direct delivery of hiPSC-CMs into the cardiac muscle layer, which was shown to induce electrical integration, was unclear because of concerns regarding poor engraftment of dispersed cardiomyocytes (CMs) and post-transplant arrhythmias. Thus, in this study, we prepared clinical-grade purified hiPSC-CM aggregates, known as cardiac spheroids (CSs), and confirmed whether the direct injection of CSs could regenerate infarcted non-human primate hearts. Methods: We performed two separate experiments to explore the appropriate number of CMs derived from human induced pluripotent stem cells (hiPSCs). In the first experiment, 10 cynomolgus monkeys were subjected to myocardial infarction 2 weeks pre-transplantation and were designated as recipients of CSs containing 2х10 7 CMs or the vehicle. The animals were killed 12 weeks post-transplantation for histological analysis, and cardiac function and arrhythmia were monitored during the observational period. In the second study, we repeated the equivalent transplantation study using more CMs (6х10 7 CMs). Results: Recipients of CSs containing 2х10 7 CMs showed limited CM grafts and transient increases in fractional shortening compared with those of the vehicle, with a low incidence of post-transplant arrhythmia. Transplantation of increased dose of CMs resulted in significantly greater engraftment and long-term contractile benefits. The incidence of post-transplant arrhythmia slightly increased in recipients of CSs containing 6х10 7 CMs. Conclusions: We demonstrated that direct injection of hiPSC-derived CSs, prepared as clinical-grade cell products, restores the contractile functions of injured primate hearts with an acceptable risk of post-transplant arrhythmia. These findings provide strong rationale for conducting clinical trials using the equivalent CM products.
Abstract P3116: Age-Related Cardiac Changes In S-Nitrosoglutathione Reductase Knockout Mice
Authors: Obialunanma V Ebenebe, Raihan Kabir, Haley Garbus, Vivek Jani, Luigi Adamo, Mark J Kohr
Journal: Circulation Research (2023)

Age associated cardiac aging differs between males and females, yet these age-related sex-dimorphic pathways remain poorly explored. We have previously shown that inhibition of S-nitrosoglutathione reductase (GSNOR) was cardioprotective during ischemic injury in male but not female mice. We therefore, hypothesized that GSNOR activity might play a role in sex-related differences in cardiac aging, and GSNOR deletion (KO) might exacerbate age-related cardiac dysfunction in females but not males. WT and KO mice underwent longitudinal 2D-echocardiography at 4, 7, 10 and 14 months of age, and echocardiographic data were analyzed with mixed-effects analysis. We saw a significant decrease in GSNOR activity in old (18 months) WT mice relative to young (4 months) in both sexes but more pronounced in males (p&lt;0.0001) vs. females (p=0.02). Left ventricular (LV) internal diameter at end-diastole significantly increased with age in WT males (2.65 ± 0.02 to 3.60 ± 0.13) and females (2.61 ± 0.02 to 3.32 ± 0.04) with a significant effect of sex across age (p&lt;0.0001). LV Mass (indexed to group body weight at 18 months) increased with age in both males (82 ± 2 to 127 ± 3) and females (85 ± 3 to 113 ± 3) with a significant age and sex interaction (p&lt;0.0001). Similar trends were observed for other echocardiographic parameters. Contrary to our hypothesis, the age- and sex-related differences observed in WT were absent in KO mice. LV internal diameter at end-diastole and LV Mass did not significantly change in male or female KO mice from 4 to 14 months of age neither did the majority of echocardiographic parameters tested. No differences were observed between male and female KO mice. Taken together, our data show that GSNOR deletion attenuates aging-induced cardiac dysfunction and abrogates age-related sex differences in the mouse heart.
Abstract P2012: Development Of An <i>In Vitro</i> Assay To Model Loss Of Neighbor At The Infarct Border Zone
Authors: Rahul Sehgal
Journal: Circulation Research (2023)

The borderzone (BZ) of the infarcted heart separates poorly-perfused areas of cell death from well-perfused territories of comparatively normal myocardium. The BZ after myocardial infarction is of key importance for the remodeling process that drives heart failure and sudden cardiac death. We recently defined the transcriptional features of the infarct borderzone using single cell RNA-Seq and spatial transcriptomics which revealed prominent upregulation of mechanotransduction transcriptional programs. A similar transcriptional response was inducible by needle trauma alone. To explain these results, we proposed the “Loss of Neighbor” (LON) Hypothesis, where surviving cells neighboring the infarct experience mechanical instability due to the highly asymmetric loss of load, leading to cell signal activation. Here, we develop and validate an in vitro model of loss of neighbor using a mechanical scratch assay to model the biology of the infarct borderzone. We cultured neonatal rat cardiomyocytes and cardiac fibroblasts and subjected them to mechanical “scratch” injury. To evaluate how the mechanical wound altered gene expression, we performed qPCR for genes expressed by cardiomyocytes in the remote zone and the borderzone using RNA isolated from cells with or without exposure to mechanical scratch injury. Compared to non-scratched cultures, scratched cells significantly upregulated BZ-specific genes such as Ankrd1, Nppa, Flnc, and Xirp2 . In addition, scratched cells significantly upregulated expression of interferon-stimulated genes (ISGs) compared to non-scratched cells or scratched cells exposed to anti-IFNAR Ab. This suggests that the interferon-inducible cell (IFNIC) response observed at the infarct borderzone in vivo can be induced by in vitro cardiomyocyte LON. Taken together, our results suggest that the mechanical scratch assay in vitro captures key elements of the transcriptional borderzone in vivo . Overall, this model can guide further elucidation of the transcriptional program states during cardiac remodeling.